Aeroplane-wing.



ALF. RUSS.

AEROPLA'NE WING. v M'PUCATION men Mma'n ms.

- WrmEssE Y INVENTOR I To all whom it may concern:

MOLE FRANK RUSS, 01F PITTSBURGH, PENNSYLVANIA.

AEBOPLANlE-WIN-G.

' Specification of Letters Patent.

Application filed March 31, 1916. Serial No. 88,126.

' provements in Aeroplane-Wings, of which improvement the following'is a specification. The object of my invention is to provide a supporting wing for aeroplanes which Wlll have a flexible lower surface capable of antomatically conforming to the curvature which will most eficiently satisfy the varying requirements of'such wings.

Tn the accompanying sheet of drawings 1 have illustrated the preferred embodiment of my invention. 7

Figure 1 is a plan view of the aeroplane wing; and Fi s. 2 and 3 are sectional views taken, respectively, on the lines ][lll and Ill-TH, Fig. 1.

In the practice of my invention 1 provide a frame to which there are secured upper and lower membranes, the lower membrane althou h stretched tautly onthe edge members o the frame, being flexible and unsupported by intermediate frame members. As far as concerns the broad features of my invention, the wing may be of any desired shape and the upper membrane may be either fixed or flexible. r

The wing shown in the drawings is triangular in shape, the frame consisting of stays 1, 2 and 3 in the forward, rearward and inner edges of the wing, braces 4: extending from the stay 3 tothe outer end or corner of the wing, and braces 5 extending between the edge stays 1 and 2. The front and rear edge stays 1 and 2 are substantially fiat members, while the inner stay 3 is of the .shape indicated by the cross-section of the wing as seen in Fig. 2, that is to say it has a convex upper side and, except for small end portions, the lower side is slightly concave. As will be seen from Figs. 2 and 3, the braces 5 are arched to conform to the generalshape of the top of the stay 3, and the braces 4 are secured to the braces 5. The upper membrane 6 is secured to and held in fixed position upon the upper side of the frame, while the lower membrane is stretched tautly between and secured to the lower edges of the stays 1, 2 and 3. The lower membrane 7 hence offers no unnecessary resistance.

lPatented ran. so, tart.

may-be made of fabric or any suitable flexible material which will yield slightly to the variable air pressure upon it.

The wing which I have shown and described may be used upon any desired form of aeroplane, but it is particularly suitable for aeroplanes such as shown in my copendmg application, Serial No; 88,127, filed of even date herewith. It isiwell' known that when'aeroplanes are gliding, or traveling in a semi-gliding manner, the usual concavity on the lower sustaining face of the wing causes an undue amount of head resistance. This undesirable feature is largely overcome by the Wing which I have provided, for the lower membrane is but slightly concave when the machine is traveling as indicated, and

the other hand, when the wing isinclined upwardly to cause the aeroplaneto rise, the increased pressure of the air against the flexible lower-membrane causes it to arch in the manner indicated by the dotted lines 9 in Figs. 2 and 3, so that the sustainingsur-- face will then'have the proper configuration to afiord the maximum lifting effect. Thus it is seen that, in the wing which I provide the variations in air pressure upon it causes the sustaining surface automatically to conform to the curvature best suited to most effectively satisfy the varying requirements.

' According to the provisions of the patent statutes, 1 have described the principle and operation of my improved aeroplane wing, together with the construction which I now consider to represent the best embodiment thereof. However, ll desire to have it understood that the wing which l[ have shown is only illustrative, and that my invention.

andintermediate cross-braces, an upper edge and gradually tapering to meeting lines membrane secured to and-held in fixed posiat the front and rear wing edges. 10 tion upon the upper side of said frame, and a flexible lower membrane stretched tautly ADOLF FRANK RUSS. 5 between and secured to the marginal stays of Witnesses:

said frame and unsupported by the other PAUL N. CRITGHLOW, frame members, said membranes being sepa- FRANCIS J. TOMASSON.

rated a substantial space at the inner wing 

